Pancreatic Islet Transplantation | NIDDK Pancreatic Islet Transplantation Pancreatic Islet Transplantation What are pancreatic islets? Pancreatic islets, also called islets of Langerhans, are tiny clusters of cells scattered throughout the pancreas. The pancreas is an organ about the size of a hand located behind the lower part of the stomach. Pancreatic islets contain several types of cells, including beta cells, that produce the hormone insulin. The pancreas also makes enzymes that help the body digest and use food. Pancreatic islets contain several types of cells, including beta cells, that produce the hormone insulin. When the level of blood glucose, also called blood sugar, rises after a meal, the pancreas responds by releasing insulin into the bloodstream. Insulin helps cells throughout the body absorb glucose from the bloodstream and use it for energy. Diabetes develops when the pancreas does not make enough insulin, the body's cells do not use insulin effectively, or both. As a result, glucose builds up in the blood instead of being absorbed by cells in the body.

In type 1 diabetes, the beta cells of the pancreas no longer make insulin because the body's immune system has attacked and destroyed them. The immune system protects people from infection by identifying and destroying bacteria, viruses, and other potentially harmful foreign substances. A person who has type 1 diabetes must take insulin daily to live. Type 2 diabetes usually begins with a condition called insulin resistance, in which the body has trouble using insulin effectively. Over time, insulin production declines as well, so many people with type 2 diabetes eventually need to take insulin. What is pancreatic islet transplantation? The two types of pancreatic islet transplantation are allo-transplantation auto-transplantation Pancreatic islet allo-transplantation is a procedure in which islets from the pancreas of a deceased organ donor are purified, processed, and transferred into another person. Pancreatic islet allo-transplantation is currently labeled an experimental procedure until the transplantation technology is considered successful enough to be labeled therapeutic. For more information, see the section "What are the obstacles to pancreatic islet allo-transplantation?" For each pancreatic islet allo-transplant infusion, researchers use specialized enzymes to remove islets from the pancreas of a single, deceased donor.

The islets are purified and counted in a lab. Transplant patients typically receive two infusions with an average of 400,000 to 500,000 islets per infusion. Once implanted, the beta cells in these islets begin to make and release insulin. Pancreatic islet allo-transplantation is performed in certain patients with type 1 diabetes whose blood glucose levels are difficult to control. The goals of the transplant are to help these patients achieve normal blood glucose levels with or without daily injections of insulin and to reduce or eliminate hypoglycemia unawareness—a dangerous condition in which a person with diabetes cannot feel the symptoms of hypoglycemia, or low blood glucose. When a person feels the symptoms of hypoglycemia, steps can be taken to bring blood glucose levels back to normal. Pancreatic islet allo-transplants are only performed at hospitals that have received permission from the U.S. Food and Drug Administration (FDA) for clinical research on islet transplantation. The transplants are often performed by a radiologist—a doctor who specializes in medical imaging.

The radiologist uses x rays and ultrasound to guide the placement of a thin, flexible tube called a catheter through a small incision in the upper abdomen—the area between the chest and hips—and into the portal vein of the liver. The portal vein is the major vein that supplies blood to the liver. The islets are then infused, or pushed, slowly into the liver through the catheter. Usually, the patient receives a local anesthetic and a sedative. In some cases, a surgeon performs the transplant using general anesthesia. Patients often need two or more transplants to get enough functioning islets to stop or reduce their need for insulin injections. Pancreatic islet allo-transplantation (above). In islet auto-transplantation, the islets are extracted from the patient's own pancreas. Pancreatic islet auto-transplantation is performed following total pancreatectomy—the surgical removal of the whole pancreas—in patients with severe and chronic, or long lasting, pancreatitis that cannot be managed by other treatments. This procedure is not considered experimental. Patients with type 1 diabetes cannot receive pancreatic islet auto-transplantation. The procedure is performed in a hospital, and the patient receives general anesthesia.

The surgeon first removes the pancreas and then extracts and purifies islets from the pancreas. Within hours, the islets are infused through a catheter into the patient's liver. The goal is to give the body enough healthy islets to make insulin. What happens after pancreatic islet transplantation? Pancreatic islets begin to release insulin soon after transplantation. However, full islet function and new blood vessel growth from the new islets take time. Transplant recipients usually take insulin injections until the islets are fully functional. They may also receive various medications before and after transplantation to promote successful implantation and long-term functioning of the islets. However, the autoimmune response that destroyed transplant recipients' own islets in the first place can happen again and attack the transplanted islets. Although the liver has been the traditional site for infusing the donor islets, researchers are investigating alternative sites, such as muscle tissue or another organ. What are the benefits and risks of pancreatic islet allo-transplantation? The benefits of pancreatic islet allo-transplantation include improved blood glucose control, reducing or eliminating the need for insulin injections to control diabetes, and preventing hypoglycemia.

An alternative to islet transplantation is whole organ pancreas transplantation that is performed most often with kidney transplantation. The advantages of whole organ pancreas transplantation are less dependence on insulin and longer duration of organ function. The main disadvantage is that a whole organ transplant is a major surgery that involves a greater risk of complications and even death. Pancreatic islet allo-transplantation can also help reverse hypoglycemia unawareness. Research has shown that even partial islet function after a transplant can eliminate hypoglycemia unawareness. Improved blood glucose control from a successful allo-transplant may also slow or prevent the progression of diabetes problems, such as heart disease, kidney disease, and nerve or eye damage. Research to evaluate this possibility is ongoing. The risks of pancreatic islet allo-transplantation include the risks associated with the transplant procedure—particularly bleeding and blood clots. The transplanted islets may not function well or may stop functioning entirely. Other risks are the side effects from the immunosuppressive medications that transplant recipients must take to stop the immune system from rejecting the transplanted islets.

When a patient has received a kidney transplant and is already taking immunosuppressive medications, the only additional risks are the islet infusion and the side effects from the immunosuppressive medications given at the time of allo-transplantation. Immunosuppressive medications are not needed in the case of an auto-transplant because the infused cells come from the patient's own body. Read more in the section "What is the role of immunosuppressive medications?" Collaborative Islet Transplant Registry Data In its 2010 annual report, 1 the Collaborative Islet Transplant Registry presented data on 571 patients who received pancreatic islet allo-transplants between 1999 and 2009. Although most procedures were pancreatic islet allo-transplants alone, 90 procedures were done in conjunction with a kidney transplant. The majority of the islet transplant patients received one or two infusions of islets; at the end of the decade, the average number of islets received per infusion was 463,000.

According to the report, about 60 percent of transplant recipients achieved insulin independence—defined as being able to stop insulin injections for at least 14 days—during the year following transplantation. By the end of the second year, 50 percent of recipients were able to stop taking insulin for at least 14 days. However, long-term insulin independence is difficult to maintain, and eventually most recipients needed to start taking insulin again. The report identified factors linked to better outcomes for recipients, including age—35 years or older lower pre-transplant triglyceride, or blood fat, levels lower pre-transplant insulin use The report noted that even partial function of the transplanted islets can improve blood glucose control and reduce the amount of insulin needed after loss of insulin independence. 1Collaborative Islet Transplant Registry seventh annual report. Collaborative Islet Transplant Registry website. (PDF, 8.2 MB) Updated December 30, 2011. Accessed July 23, 2013. What is the role of immunosuppressive medications? Immunosuppressive medications are needed to prevent rejection—a common problem with any transplant.

Scientists have made many advances in islet transplantation in recent years. In 2000, islet transplantation researchers at the University of Alberta in Edmonton, Canada, reported their findings in the New England Journal of Medicine. Their transplant protocol, known as the Edmonton protocol, has since been adapted by transplant centers around the world and continues to be refined. The Edmonton protocol introduced the use of a new combination of immunosuppressive medications, also called anti-rejection medications, including daclizumab (Zenapax), sirolimus (Rapamune), and tacrolimus (Prograf). Researchers continue to develop and study modifications to the Edmonton protocol, including improved medication regimens that promote successful transplants. Medication regimens vary from one transplant center to another. Examples of other immunosuppressive medications used in islet transplantation include antithymocyte globulin (Thymoglobulin), alemtuzumab (Campath), basiliximab (Simulect), belatacept (Nulojix), etanercept (Enbrel), everolimus (Zortress), and mycophenolate mofetil (CellCept, Myfortic).

Researchers are also evaluating nonimmunosuppresive medications, such as exenatide (Byetta) and sitagliptin (Januvia). Immunosuppressive medications have significant side effects, and their long-term effects are still not fully known. Immediate side effects may include mouth sores and gastrointestinal problems, such as upset stomach and diarrhea. Patients may also have increased blood cholesterol, or blood fat, levels high blood pressure anemia, a condition in which red blood cells are fewer or smaller than normal, which prevents the body's cells from getting enough oxygen fatigue decreased white blood cell counts decreased kidney function increased susceptibility to bacterial and viral infections Taking immunosuppressive medications also increases the risk of developing certain tumors and cancers. Scientists are seeking ways to achieve immune tolerance of the transplanted islets, in which the patient's immune system no longer recognizes the islets as foreign. Immune tolerance would allow patients to maintain transplanted islets without long-term use of immunosuppressive medications. For example, one approach is to transplant islets encapsulated with a special coating, which may help to prevent rejection. What are the obstacles to pancreatic islet allo-transplantation?

The shortage of islets from donors is a significant obstacle to widespread use of pancreatic islet allo-transplantation. According to the Organ Procurement and Transplantation Network, in 2011 there were about 8,000 deceased organ donors available in the United States. 2 However, only 1,562 pancreases were recovered from donors in 2011. 2 Also, many donated pancreases are not suitable for extracting islets for transplants because they do not meet the selection criteria, and islets are often damaged or destroyed during processing. Therefore, only a small number of islet transplants can be performed each year. Researchers are pursuing various approaches to solve this shortage of islets, such as transplanting islets from a single, donated pancreas, using only a portion of the pancreas from a living donor, or using islets from pigs. Researchers have transplanted pig islets into other animals, including monkeys, by encapsulating the islets with a special coating or by using medications to prevent rejection. Another approach is creating islets from other types of cells, such as stem cells. New technologies could then be employed to grow islets in the lab.

Financial barriers also prevent the widespread use of islet allo-transplantation. Until the transplantation technology is considered successful enough to be labeled therapeutic rather than experimental, the costs of islet allo-transplants must be covered by research funds. Health insurance companies and Medicare generally do not cover experimental procedures. Federal law also does not allow health care providers or hospitals to charge patients or health insurance companies for research procedures. Some patient advocates and islet researchers feel that islet allo-transplantation is close to having a therapeutic label. The National Institutes of Health (NIH) currently supports studies that are working toward obtaining FDA licensure to reclassify islet allo-transplantation as therapeutic. In other countries, such as Canada and Scandinavia, islet allo-transplantation is no longer considered experimental and is an accepted therapy in certain patients. 2National data. Organ Procurement and Transplantation Network website. . Accessed July 23, 2013. Eating, Diet, and Nutrition A person who receives a pancreatic islet transplant should follow a meal plan worked out with a health care provider and dietitian. Immunosuppressive medications taken after the transplant can cause changes in a person's body, such as weight gain.

A healthy diet after the transplant is important to control weight gain, blood pressure, blood cholesterol, and blood glucose levels. Points to Remember Pancreatic islets, also called islets of Langerhans, are tiny clusters of cells scattered throughout the pancreas. Pancreatic islets contain several types of cells, including beta cells, that produce the hormone insulin. Insulin helps cells throughout the body absorb glucose from the bloodstream and use it for energy. Pancreatic islet allo-transplantation is a procedure in which islets from the pancreas of a deceased organ donor are purified, processed, and transferred into another person. Pancreatic islet allo-transplantation is performed in certain patients with type 1 diabetes whose blood glucose levels are difficult to control. The goals of the transplant are to help these patients achieve normal blood glucose levels with or without daily injections of insulin and to reduce or eliminate hypoglycemia unawareness. Pancreatic islet auto-transplantation is performed following total pancreatectomy in patients with severe and chronic pancreatitis that cannot be managed by other treatments. This procedure is not considered experimental. Patients with type 1 diabetes cannot receive pancreatic islet auto-transplantation.

The shortage of islets from donors is a significant obstacle to widespread use of pancreatic islet allo-transplantation. Financial barriers also prevent the widespread use of islet allo-transplantation. Until the transplantation technology is considered successful enough to be labeled therapeutic rather than experimental, the costs of islet allo-transplants must be covered by research funds. Clinical Trials The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and other components of the National Institutes of Health (NIH) conduct and support research into many diseases and conditions. What are clinical trials, and are they right for you? Clinical trials are part of clinical research and at the heart of all medical advances. Clinical trials look at new ways to prevent, detect, or treat disease. Researchers also use clinical trials to look at other aspects of care, such as improving the quality of life for people with chronic illnesses. Find out if clinical trials are right for you . What clinical trials are open? Clinical trials that are currently open and are recruiting can be viewed at . September 2013 PDF Version (290 KB) You can also order print versions from our online catalog.

This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings through its clearinghouses and education programs to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts. The NIDDK would like to thank: Marlon Levy, M.D., medical director of the Pancreas and Islet Cell Laboratory, Baylor University Medical Center and Baylor All Saints Medical Center This information is not copyrighted. The NIDDK encourages people to share this content freely. Contact Us Transplant Surgery - Islet Transplant for Type 1 Diabetes Transplant Surgery » Conditions & Procedures » Islet Transplant for Type 1 Diabetes FOLLOW Sign up for delivery of news Islet Transplant for Type 1 Diabetes Islet cell transplantation places cells from an organ donor into the body of another person.

It is used experimentally to treat type 1 diabetes Image Courtesy of UCSF Diabetes Education Online Pancreatic Islets and Beta Cells The pancreas is an organ about the size of a hand located in the abdomen in the vicinity of the stomach, intestines, and other organs. It lies behind the stomach and in front of the spine. The pancreas produce juices that help digest food and hormones such as insulin and glucagon that maintain optimal blood sugar levels and help the body to use and store energy from food. Throughout the pancreas are clusters of cells called the islets of Langerhans. Islets are made up of several types of cells, including beta cells that make insulin. Insulin is a hormone that helps the body use glucose for energy. Insulin and Diabetes Diabetes develops when the body doesn't make enough insulin, cannot use insulin properly, or both, causing glucose to build up in the blood. Diabetes is a serious disease, which, if not controlled, can be life threatening. It is often associated with long-term complications that can affect every system and part of the body. Diabetes can contribute to eye disorders and blindness, heart disease, stroke, kidney failure, amputation, and nerve damage.

Type 1 Diabetes Type 1 diabetes results from the body's failure to produce insulin, the hormone that "unlocks" the cells of the body, allowing glucose to enter and fuel them. It is an autoimmune disease in which the body views the beta cells (insulin producing cells found in the islets of the pancreas) as a foreign substance, so the patient's immune system attacks the islets and kills them. It is estimated that 5-10% of Americans who are diagnosed with diabetes have type 1 diabetes. Most people with type 1 diabetes do not have a family history of the disease and there is no way currently to prevent the onset of type1 diabetes. Image courtesy of Clinical Islet Transplantation (CIT) Consortium, sponsored by National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK) and National Institute of Allergy and Infectious Diseases (NIAID) Insulin therapy, given by injection or insulin pump, is life-saving. However, it's not perfect. Most people with type 1 diabetes still have blood glucose levels that are above normal. This puts them at risk for the long-term complications of diabetes. Some people have what doctors call labile, or brittle, diabetes.

Blood glucose levels swing from high to low despite the best insulin plans. Because of this, long-term type 1 diabetic survivors often develop vascular complications, such as diabetic retinopathy, an eye disease that can cause poor vision and blindness, and diabetic nephropathy, a kidney disease that can lead to kidney failure. Hypoglycemia Unawareness Those who are able to keep their blood glucose levels near normal often have trouble with low blood glucose (hypoglycemia). And after many years, some people lose the early symptoms that warn them that their blood glucose level is dropping. This is called hypoglycemia unawareness and raises the risk of severe hypoglycemia. Hypoglycemia unawareness is a life-threatening condition that is not easily treatable with medication and is characterized by reduced or absent warning signals for hypoglycemia. Some Type 1 diabetic patients have been known to set their alarms to wake them several times a night out of fear they may have a catastrophic hypoglycemic episode while asleep. For such individuals, transplantation of pancreatic islets is a viable treatment option to consider.

Islet Cell Transplantation Procedure In islet transplantation, islets are taken from the pancreas of a deceased organ donor. The islets are purified, processed, and transferred into another person. Once implanted, the beta cells in these islets begin to make and release insulin. Researchers hope that islet transplantation will help people with type 1 diabetes live without daily injections of insulin. Researchers use specialized enzymes to remove islets from the pancreas of a deceased donor. Because the islets are fragile, transplantation occurs soon after they are removed. Typically a patient receives at least 10,000 islet "equivalents" per kilogram of body weight, extracted from two donor pancreases. Patients often require two transplants to achieve insulin independence. Some transplants have used fewer islet equivalents taken from a single donated pancreas. Transplants are often performed by a radiologist, who uses x rays and ultrasound to guide placement of a catheter-a small plastic tube-through the upper abdomen and into the portal vein of the liver. The islets are then infused slowly through the catheter into the liver. The patient receives a local anesthetic and a sedative.

In some cases, a surgeon may perform the transplant through a small incision, using general anesthesia. Islets extracted from a donor pancreas are infused into the liver. Once implanted, the beta cells in the islets begin to make and release insulin. Image courtesy of University of Alberta and the Clinical Islet Transplantation (CIT) Consortium, sponsored by National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK) and National Institute of Allergy and Infectious Diseases (NIAID) Islets begin to release insulin soon after transplantation. However, full islet function and new blood vessel growth associated with the islets take time. The doctor will order many tests to check blood glucose levels after the transplant, and insulin is usually given until the islets are fully functional. Benefits and Risks Islet Transplantation Benefits The goal of islet transplantation is to infuse enough islets to control the blood glucose level without insulin injections. Other benefits may include improved glucose control and prevention of potentially dangerous episodes of hypoglycemia.

Because good control of blood glucose can slow or prevent the progression of complications associated with diabetes, such as heart disease, kidney disease, and nerve or eye damage, a successful transplant may reduce the risk of these complications. Risks Risks of islet transplantation include the risks associated with the transplant procedure-particularly bleeding and blood clots-and side effects from the immunosuppressive drugs that transplant recipients must take to stop the immune system from rejecting the transplanted islets. Most people need two infusions at different times to get enough islets that are working, and some need three. So, even if islet transplantation is found to be effective, currently, there are not enough donor pancreases available to treat everyone with type 1 diabetes. Immunosuppression and Rejection As with any organ transplant, the recipient of an islet transplant must take drugs every day to keep the body from rejecting the islets. The immune system is programmed to destroy bacteria, viruses, and tissue it recognizes as "foreign," including transplanted islets. In addition, the autoimmune response that destroyed transplant recipients' own islets in the first place can recur and attack the transplanted islets. These drugs put the person at risk for infections and certain cancers.

They can also cause side effects that range from mild to severe. Some people who received an islet transplant have had to stop taking these medications, because of side effects and then their new islets stopped working. New Immunosuppression Protocols The Edmonton protocol introduced the use of a new combination of immunosuppressive drugs, also called anti-rejection drugs, including daclizumab (Zenapax), sirolimus (Rapamune), and tacrolimus (Prograf). Daclizumab is given intravenously right after the transplant and then discontinued. Sirolimus and tacrolimus, the two main drugs that keep the immune system from destroying the transplanted islets, must be taken for life or for as long as the islets continue to function. These drugs have significant side effects and their long-term effects are still not fully known. Immediate side effects of immunosuppressive drugs may include mouth sores and gastrointestinal problems, such as stomach upset and diarrhea. Patients may also have increased blood cholesterol levels, hypertension, anemia, fatigue, decreased white blood cell counts, decreased kidney function, and increased susceptibility to bacterial and viral infections. Taking immunosuppressive drugs also increases the risk of tumors and cancer.

Researchers continue to develop and study modifications to the Edmonton protocol drug regimen, including the use of new drugs and new combinations of drugs designed to help reduce destruction of transplanted islets and promote their successful implantation. These therapies may help transplant recipients achieve better function and durability of transplanted islets with fewer side effects. The ultimate goal is to achieve immune tolerance of the transplanted islets, where the patient's immune system no longer recognizes the islets as foreign. If achieved, immune tolerance would allow patients to maintain transplanted islets without long-term immunosuppression. Researchers are also trying to find new approaches that will allow successful transplantation without the use of immunosuppressive drugs. For example, one study is testing the transplantation of islets that are encapsulated with a special coating designed to prevent rejection. Shortage of Islets A major obstacle to widespread use of islet transplantation is the shortage of islets. Although organs from about 7,000 deceased donors become available each year in the United States, fewer than half of the donated pancreases are suitable for whole organ pancreas transplantation or for harvesting of islets-enough for only a small percentage of those with type 1 diabetes.

However, researchers are pursuing various approaches to solve this problem, such as transplanting islets from a single donated pancreas, from a portion of the pancreas of a living donor, or from pigs. Researchers have transplanted pig islets into other animals, including monkeys, by encapsulating the islets or by using drugs to prevent rejection. Another approach is creating islets from other types of cells, such as stem cells. New technologies could then be employed to grow islets in the laboratory. Note: The information above was reproduced or derived from the following public domain sources: The National Digestive Diseases Information Clearinghouse (NDDIC) , the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Reference Collection, and MedlinePlus, a service of the National Library of Medicine and National Institutes of Health (NIH), The Clinical Islet Transplantation (CIT) Consortium is a network of clinical centers and a data coordinating center established in 2004 to conduct studies of islet transplantation in patients with type 1 diabetes, also funded by the NIH and NIDDK, and Diabetes Education Online, UCSF Diabetes Teaching Center's Diabetes Education Online.

FOLLOW Islet Cells: Islets of Langerhans: Pancreatic Cell What are Islet Cells? The Islets of Langerhans The Islets of Langerhans are commonly referred to as "islets" (pronounced "EYE-lets"). Islets actually are clusters of cells, with each "islet" containing 3,000 to 4,000 cells. Scientists estimate there are 1 million islets in a healthy, adult pancreas. They make up only 1 to 2 percent of the entire organ. Within each islet are several types of cells, which work together to regulate blood sugar. One cell type is the beta cell. Beta cells sense sugar in the blood and release the necessary amount of insulin to maintain normal blood sugar levels. The immune system mistakenly sees beta cells as "potential danger" and destroys them, causing type 1 diabetes . The loss of these cells means the body can no longer produce insulin, the hormone required to convert food into energy for the body’s cells. Although insulin-producing islet cells cease to function in persons with diabetes, the remaining 98 percent of the pancreas continues to function normally, producing digestive enzymes.

Here at the DRI, we’re focused on restoring natural insulin production to normalize blood sugar control. One key strategy is islet transplantation -- taking healthy islets from a donor pancreas and transplanting them into patients with diabetes. We’ve already demonstrated that transplanted islets can function for more than 12 years. Much of our research is now aimed at increasing the supply of islet cells available for transplantation, to find the optimal site for transplantation, as well as eliminating the need for anti-rejection drugs . Islets are clusters of cells scattered throughout the pancreas, which include cells that sense sugar in the blood. Do you know how islet cells are isolated from the pancreas? View this video about the innovative method developed by DRI Director Dr. Camillo Ricordi that makes islet cell transplantation possible. Islets of Langerhans are made of four different cell types. The majority are insulin-producing beta cells (shown in green) and glucagon-producing alpha cells (shown in red). The blue color is a marker used to locate the nucleus of the cells. Using Laser Scanning Cytometry (LSC), DRI scientists can study the physiology of the basic islet components to assess their viability before transplantation.

islets of Langerhans | anatomy | Britannica.com Islets of Langerhans Alternative Titles: islands of Langerhans, pancreatic islets Related Topics endocrine system Islets of Langerhans, also called islands of Langerhans, irregularly shaped patches of endocrine tissue located within the pancreas of most vertebrates. They are named for the German physician Paul Langerhans, who first described them in 1869. The normal human pancreas contains about 1,000,000 islets. The islets consist of four distinct cell types, of which three (alpha, beta, and delta cells) produce important hormones ; the fourth component (C cells) has no known function. The islets of Langerhans are responsible for the endocrine function of the pancreas. Each islet … Encyclopædia Britannica, Inc. The most common islet cell, the beta cell, produces insulin , the major hormone in the regulation of carbohydrate, fat, and protein metabolism.

Insulin is crucial in several metabolic processes: it promotes the uptake and metabolism of glucose by the body’s cells; it prevents release of glucose by the liver; it causes muscle cells to take up amino acids, the basic components of protein; and it inhibits the breakdown and release of fats. The release of insulin from the beta cells can be triggered by growth hormone (somatotropin) or by glucagon, but the most important stimulator of insulin release is glucose; when the blood glucose level increases—as it does after a meal—insulin is released to counter it. The inability of the islet cells to make insulin or the failure to produce amounts sufficient to control blood glucose level are the causes of diabetes mellitus . The islets of Langerhans contain alpha, beta, and delta cells that produce glucagon, insulin, and … Encyclopædia Britannica, Inc. The alpha cells of the islets of Langerhans produce an opposing hormone, glucagon , which releases glucose from the liver and fatty acids from fat tissue. In turn, glucose and free fatty acids favour insulin release and inhibit glucagon release.

The delta cells produce somatostatin , a strong inhibitor of somatotropin, insulin, and glucagon; its role in metabolic regulation is not yet clear. Somatostatin is also produced by the hypothalamus and functions there to inhibit secretion of growth hormone by the pituitary gland . Learn More in these related articles: Islets of Langerhans - RightDiagnosis.com Islets of Langerhans Descriptions of Islets of Langerhans Islets of Langerhans: cell clusters in the pancreas that form the endocrine part of that organ; secrete insulin and other hormones Source: WordNet 2.1 Summary Information: Islets of Langerhans Islets of Langerhans: The islets of Langerhans are a specialized group of cells located in the pancreas, an endocrine organ located in the upper left area of the abdominal cavity. As a group, the islets of Langerhans produce pancreatic hormones including glucagon, insulin, and somatostatin. The islets of Langerhans include the alpha cells, beta cells, and delta cells.

Conditions that can afflict the islets of Langerhans include pancreatic cancer, type 1 diabetes, type 2 diabetes, and pancreatitis. Closely Related Organs: Islets of Langerhans The following organs are closely related to the organ: Islets of Langerhans: Insulin | Gondar Design Biology Gondar Design Biology The Eye Insulin Insulin is a hormone, that means it is a chemical secreted into the blood by an endocrine organ and carried around the body to a target organ. Insulin helps to control the amount of glucose dissolved in the blood. Insulin prevents the blood sugar level from rising too high. It is also necessary to have insulin in your blood for respiration to take place. Without insulin cells can only get energy from fat and this causes serious problems. The control of blood sugar level is a homeostatic mechanism. How Insulin Works: Insulin is secreted by the Islets of Langerhans which are special groups of cells in the pancreas. The Islets (little islands) are endocrine organs.

If you have a large carbohydrate meal, the level of glucose in the blood will start to rise as your digestive system turns all the starch and sugars in your food into glucose. If you have not had a meal for several hours your blood sugar level will fall because your cells use up the glucose in aerobic respiration. When your blood sugar level rises, the Islets of Langerhans secrete MORE insulin. When your blood sugar level falls, the Islets of Langerhans secrete LESS insulin. The main target organ for insulin is the liver. It is the liver which removes glucose from the blood by turning it into glycogen. All other tissues in your body need insulin to help then respire glucose, so in a way they are also target organs. If you eat, and eat, and eat, and eat, never mind how little exercise; there will come a time when there is no more room for glycogen in your liver. High levels of insulin will make you start to turn the excess glucose into FAT. Please balance your diet!!!!! When you fast for more than two days, your liver will run out of glycogen, so you will have to use fat and protein to get energy.

When your blood sugar level falls too low, not only does the pancreas make less insulin, but another endocrine gland, the adrenal gland, starts to make adrenalin and glucocorticoids. Adrenalin and glucocorticoids are hormones which have the opposite effect to insulin, i.e. they help to raise blood sugar level. The hypothalamus detects the conditions in your blood. It measures many things including blood sugar level. The hypothalamus is connected to the pituitary gland which is yet another endocrine gland. Negative feedback is the special mechanism for turning the hormones off after they have done their job. So when your blood sugar level drops, the amount of insulin produced also falls, and when your blood sugar level has risen back to normal, the amount of adrenalin and glucocorticoids falls. Definitions: Hormone: this is a chemical secreted directly into the blood by an endocrine organ, it carries a message to a target organ. A hormone is a chemical messenger. Endocrine Organ: this is an organ which secretes a chemical messenger or hormone directly into the blood. (c.f. an exocrine organ.) Endocrine organs make hormones. Target Organ: this is any organ which is affected by a hormone.

Almost every organ in the body is affected by one or more hormones. Target organs ar controlled by hormones. Hypothalamus: this is a region at the base of the brain which monitors the conditions of your blood. It measures how much water, salts, bicarbonate ions and sugar is present; it also measures blood temperature. The hypothalamus helps to control the pituitary gland. Pituitary Gland: this is the Master Endocrine Gland. It secretes hormones which control other endocrine glands. Homeostasis: this is the mechanism for keeping your internal conditions constant. Blood sugar control is one example of homeostasis/a homeostatic mechanism. The other important ones are: osmoregulation, & thermoregulation. Negative feedback: this is exactly the opposite of positive feedback! Another page in this Web Site to explain it. It is a switching off mechanism. Pancreatic Islet Transplant Surgery,Pancreatic Islet Transplant India Overview What Are Pancreatic Islets? The pancreas, an organ about the size of a hand, is located behind the lower part of the stomach. It makes insulin and enzymes that help the body digest and use food.

Throughout the pancreas are clusters of cells called the islets of Langerhans. Islets are made up of several types of cells, including beta cells that make insulin. The pancreas is located in the abdomen behind the stomach. Islets within the pancreas contain beta cells, which produce insulin. Insulin is a hormone that helps the body use glucose for energy. Diabetes develops when the body doesn’t make enough insulin, cannot use insulin properly, or both, causing glucose to build up in the blood. In type 1 diabetes—an autoimmune disease—the beta cells of the pancreas no longer make insulin because the body’s immune system has attacked and destroyed them. A person who has type 1 diabetes must take insulin daily to live. Type 2 diabetes usually begins with a condition called insulin resistance, in which the body has difficulty using insulin effectively. Over time, insulin production declines as well, so many people with type 2 diabetes eventually need to take insulin. What Are The Benefits And Risks Of Islet Transplantation ? The goal of islet transplantation is to infuse enough islets to control the blood glucose level without insulin injections. Other benefits may include improved glucose control and prevention of potentially dangerous episodes of hypoglycemia.

Because good control of blood glucose can slow or prevent the progression of complications associated with diabetes, such as heart disease, kidney disease, and nerve or eye damage, a successful transplant may reduce the risk of these complications. Risks of islet transplantation include the risks associated with the transplant procedure—particularly bleeding and blood clots—and side effects from the immunosuppressive drugs that transplant recipients must take to stop the immune system from rejecting the transplanted islets. Transplant Procedure Transplants are often performed by a radiologist, who uses x rays and ultrasound to guide placement of a catheter—a small plastic tube—through the upper abdomen and into the portal vein of the liver. The islets are then infused slowly through the catheter into the liver. The patient receives a local anesthetic and a sedative. In some cases, a surgeon may perform the transplant through a small incision, using general anesthesia. Islets begin to release insulin soon after transplantation. However, full islet function and new blood vessel growth associated with the islets take time. The doctor will order many tests to check blood glucose levels after the transplant, and insulin is usually given until the islets are fully functional. What Are The Benefits And Risks Of Islet Transplantation ?

The goal of islet transplantation is to infuse enough islets to control the blood glucose level without insulin injections. Other benefits may include improved glucose control and prevention of potentially dangerous episodes of hypoglycemia. Because good control of blood glucose can slow or prevent the progression of complications associated with diabetes, such as heart disease, kidney disease, and nerve or eye damage, a successful transplant may reduce the risk of these complications. Risks of islet transplantation include the risks associated with the transplant procedure—particularly bleeding and blood clots—and side effects from the immunosuppressive drugs that transplant recipients must take to stop the immune system from rejecting the transplanted islets. For more information, medical assessment and medical quote as email attachment to Contact Center Tel. (+91) 9029304141 (10 am. To 8 pm.

IST) (Only for international patients seeking treatment in India) Islets of Langerhans - RightDiagnosis.com Islets of Langerhans Introduction: Islets of Langerhans Description of Islets of Langerhans Islets of Langerhans: cell clusters in the pancreas that form the endocrine part of that organ; secrete insulin and other hormones. Source: WordNet 2.1 Islets of Langerhans: Irregular microscopic structures consisting of cords of endocrine cells that are scattered throughout the PANCREAS among the exocrine acini. Each islet is surrounded by connective tissue fibers and penetrated by a network of capillaries. There are four major cell types. The most abundant beta cells (50-80%) secrete INSULIN . Alpha cells (5-20%) secrete GLUCAGON . PP cells (10-35%) secrete PANCREATIC POLYPEPTIDE . Delta cells (~5%) secrete SOMATOSTATIN . Source: MeSH 2007 Islets of Langerhans: Related Topics These medical condition or symptom topics may be relevant to medical information for Islets of Langerhans:

Question: In which organ of the body are the 'Islets of Langerhans'?
Answer: THE PANCREAS